These kinds of stars are called SPECTROSCOPIC BINARIES.

这类恒星被称为分光双星。

Even better: Alcor is a spectroscopic binary, too!

开阳伴星也是分光双星！

In even a small telescope you can see that Mizar is actually a visual binary… but it turns out that both of those two stars making up Mizar are actually SPECTROSCOPIC binaries, too.

即使是用一个小望远镜，你也可以看到开阳星实际上是目视双星… … 但事实证明，组成开阳星的这两颗恒星其实也是分光双星。